This. Do not use a 540 pin roller unless you are completely bald.If you use a 1.5 m 192 pin roller, you can roll over your hair and it will not cut or pull it. Roll in the direction the hair is laying so, for example, if you have your hair combed back, then start in the front at the hairline and roll back from the hairline. Do Not Use a 540 pin roller. It will cut and pull your hair out. I have noticed only 1 cut hair with a 192 pin roller in 5 sessions. And I roll hard and have blood red hair when I'm done.